Mercuric Iodide (HgI.sub.2) single crystals have long been thought to have potential as a material for solid state x-ray detectors for many spectrometeric applications. But, to date have been characterized by limited reliability, low energy resolution, and low yields. Thus, they have not achieved significant commercial success.
Specifically, prior art Mercuric Iodide detectors have been characterized by a very small active areas (1-2 mm.sup.2), high background levels in the x-ray spectral responses, instabilities in the detector leakage currents, limited detector life-times and reliability. All above problems of prior art detectors are related to the improper detector construction, poor surface passivation/encapsulation and poor packaging.